4,222 Introduction to Programming

Exercise Week 1: Getting started

Author

Aurélien Sallin

Published

February 20, 2025

Exercise 1: Set up your course directory

Create a directory for the course on your computer: Introduction_to_programming using the terminal. This directory will be your local directory containing your exercises, course materials, and group project. We suggest that we all work with the same directory names to make collaboration and debugging easier.

To create the directory, use command prompt or powershell to first navigate to the path you want to create the directory using cd, then create the directory using mkdir.

We will have the following folder structure throughout the course. Notice our personal preference for snake case.

Introduction_to_programming/
├── github_course_materials/ # is empty for now, you will clone the git repo in week 3
├── exercises/               # Student's own work
│   ├── week_01/
│   ├── week_02/
│   ├── ...
│   ├── week_12/
├── group_project/
│   ├── ...

where Introduction_to_programming is the main folder, github_course_materials will be created next week with git, and group_project will contain students’ own work.

For instance, in Powershell, starting from my home directory ~, which is C:/Users/aurel:

C:\Users\aurel>cd OneDrive/Documents

C:\Users\aurel\OneDrive\Documents>mkdir Introduction_to_programming

C:\Users\aurel\OneDrive\Documents>cd Introduction_to_programming

C:\Users\aurel\OneDrive\Documents\Introduction_to_programming>mkdir github_course_materials

C:\Users\aurel\OneDrive\Documents\Introduction_to_programming>mkdir exercises

C:\Users\aurel\OneDrive\Documents\Introduction_to_programming>cd exercises

C:\Users\aurel\OneDrive\Documents\Introduction_to_programming\exercises>mkdir week_01

C:\Users\aurel\OneDrive\Documents\Introduction_to_programming\exercises>mkdir week_02

C:\Users\aurel\OneDrive\Documents\Introduction_to_programming\exercises>cd ..

C:\Users\aurel\OneDrive\Documents\Introduction_to_programming>dir
 Volume in drive C is Windows-SSD
 Volume Serial Number is 2E13-E362

 Directory of C:\Users\aurel\OneDrive\Documents\Introduction_to_programming

14/02/2026  10:28    <DIR>          .
14/02/2026  10:27    <DIR>          ..
14/02/2026  10:28    <DIR>          exercises
14/02/2026  10:28    <DIR>          github_course_materials
               0 File(s)              0 bytes
               4 Dir(s)  304’672’137’216 bytes free


Exercise 2: Install VS Code

Now install VSCode on your computer. Follow instructions online. Then create the “data science profile” in VSCode. See here for an introduction: https://code.visualstudio.com/docs/configure/profiles

2.1. Open VSCode in your course directory

You should always make VS Code start from the directory your are working in. You can do this in the following ways:

  1. Either use your terminal and navigate to Introduction_to_programming using cd. Then use code . to open VS code in your directory.
  2. You can also open VS Code, and then use File/Open Folder.

The solution to this exercise will be shown during the exercise session. Here is a preview of how to open VS Code from the terminal:

2.2. Open a terminal in VSCode

An advantage of using VS Code is that you can use the terminal directly in VS Code. This allows you to have your code and your terminal in the same window, which is very convenient.

In VS Code, open a terminal. Notice that you can choose between powershell or command prompt in Windowns, or bash in MacOs. In the terminal, understand where you are located. Find your current path directory using pwd.

The solution to this exercise will be shown during the exercise session. Here is a preview of how to open a terminal in VS Code:

2.3. Get familiar with VS Code

Take time to explore VS Code. Notice the left bar. In this bar, the first tab is to access all your files and folders within your directory (the directory in which VSCode is rooted). There is also a tab for extensions, etc.

Install the following extensions (these help Python work better in VS Code):

  • Python (Microsoft)
  • Pylance (Microsoft)
  • Ruff
  • Jupyter

The solution to this exercise will be shown during the exercise session.

2.4. Create and remove a file

Using your terminal, create a file “hello.txt” in the exercises/week_01 folder. Remove the file “hello.txt”. After this, move your working directory back to Introduction_to_programming.

C:/Users/aurel/OneDrive/Documents/Introduction_to_programming> cd exercises/week_01

# Solution 1 for bash users (git bash or MacOS): create the file hello.txt
C:/Users/aurel/OneDrive/Documents/Introduction_to_programming/exercises/week_01> touch hello.txt
C:/Users/aurel/OneDrive/Documents/Introduction_to_programming/exercises/week_01> rm hello.txt

# Solution 2 for Command Prompt users in Windows: create the file hello.txt
C:/Users/aurel/OneDrive/Documents/Introduction_to_programming/exercises/week_01> echo. > hello.txt
C:/Users/aurel/OneDrive/Documents/Introduction_to_programming/exercises/week_01> del hello.txt

# Move back to Introduction_to_programming
C:/Users/aurel/OneDrive/Documents/Introduction_to_programming/exercises/week_01> cd ../..


Exercise 3: Install python via uv

You can use the following commands in your terminal to set everything up. Remember, left click works like copy-paste in many terminals. Go on the uv website for more information on how to install.

3.1. Install uv

# Install uv using standalone installer
powershell -ExecutionPolicy ByPass -c "irm https://astral.sh/uv/install.ps1 | iex"

# Add uv to PATH (follow instructions in the terminal)
$env:PATH = $env:PATH + ";$env:USERPROFILE\.local\bin"

# Make the PATH change permanent
[Environment]::SetEnvironmentVariable("PATH", $env:PATH + ";$env:USERPROFILE\.local\bin", "User")

# Verify installation
uv
# Install uv standalone installer
curl -LsSf https://astral.sh/uv/install.sh | sh

# Or using pip
pip install uv

# Verify installation
uv --version

Then check if it works in your terminal:

uv

You should see something like this:

PS C:/.../Introduction_to_programming> uv
An extremely fast Python package manager.

Usage: uv.exe [OPTIONS] <COMMAND>

Commands:
  auth     Manage authentication
  run      Run a command or script
  init     Create a new project
  add      Add dependencies to the project
  ...


3.2. [Optional] Install python using uv

Now, we can install python. If Python is already installed on your system (on Windows mostly the case), uv will detect and use it without configuration.

uv init will automatically download Python to uv’s managed directory if needed. If you need to install python, you can also do it manually with the following command:

uv python install

We will use Python 3.


3.3. Create a project for the exercise

Remember, in the lecture we mentioned the importance of “closed environments” for Python. This is different than in R. We will create a new environment for each exercise session. To create a closed environment, we use a project with uv, which will manage our python version and our packages.

In the terminal, make sure you are in your working directory ~/Introduction_to_programming/exercises/week_01. Use uv init to initialize your project. Then specify the version of python we will use in this environment. We will use python 3.14.1 (for this course, it does not matter much).

cd ~/OneDrive/Documents/Introduction_to_programming/exercises/week_01
uv init --python 3.14.1

You should observe the creation of different files:

Introduction_to_programming/exercises/week_01/
├── .python-version          # Specifies Python version (3.14.1) for this project
├── pyproject.toml           # Project configuration file. Defines project dependencies and settings
├── .gitignore               # Instructions for git. We will see this next week.
├── README.md                #  README text file that contains your basic project documentation. Feel free to add some information. The syntax is `markdown` (`md`) syntax.
└── main.py                  # Example Python script, can be erased

Now, we will install the following python packages in our environment: ipykernel, pandas, numpy. Install them using uv add

uv add ipykernel pandas numpy

You should observe different things happening:

  • the creation of a .venv folder, which contains your isolated Python environment
  • the creation of a uv.lock file, which “locks” the exact versions of all dependencies
  • your file pyproject.toml being updated under “dependencies”`1

The solution to this exercise will be shown during the exercise session. Here is a preview of how to init uv and add dependencies:


3.4 Open python using uv

Open python with your terminal using uv run python.

The solution to this exercise will be shown during the exercise session. Here is a preview of how to run python in your uv environment:


3.5 Using a python script in VS code

Once in Introduction_to_programming/exercises/week_01, open the main.py. The trick now is to choose the right python interpreter. Python interpreters are programs that read and execute your Python code. Each environment can have its own interpreter, which ensures you use the correct Python version and packages for your project. Since we defined our Python installation, we need to select the interpreter we chose from our uv environment.

  • In VS Code, use CTRL/CMD + SHIFT + P to open the palette. Then write “Select Python Interpreter”. There will be a list of available Python interpreters. Chose the one corresponding to Python 3.14.1 in your venv (tagged “Workspace” by VS Code).

Note: it could be that VSCode does not detect your interpreter right away. In this case, first try to refresh VSCode using CTRL/CMD + SHIFT + P and then “Developer: Reload Window”. Otherwise, select “Enter interpreter path” and navigate to the venv folder in your project, then select the python.exe file in this folder.

The solution to this exercise will be shown during the exercise session. Here is a preview of how to select the right python interpreter in VS Code:

  • In VS Code, if you have a .py file open, check the Python interpreter at the bottom right and make sure you have the right one selected.

The solution to this exercise will be shown during the exercise session. Here is a preview of how to select the right python interpreter in VS Code:


Exercise 4: Create a Python script

Create a first python script called hello.py, which contains the command print('hello world'). Run it from the script and run it with uv using the following command:

uv run hello.py

In the python file, right click and select “Run in Interactive Window”. You’ve run your first Python script of the course. 🎊


Using the terminal be like

Footnotes

  1. Note that uv.lock + pyproject.toml replace the traditional requirements.txt in pip. You can generate a requirements.txt file from uv using uv pip freeze > requirements.txt.↩︎